Label them 'impaired'

Forty-nine lakes and 43 streams in the Upper Mississippi River Basin have been added to the 2006 impaired waters list by the Minnesota Pollution Control Agency.

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The updated list was presented Wednesday during a public meeting at the Brainerd office of the MPCA. It includes 396 new waters statewide, bringing the total number on the list to 2,274.

"Impaired" means the water has pollutant levels that prohibit it from meeting its designated uses for fishing, swimming and aquatic habitat.

Area waters new to the list include Margaret Lake in Cass County; First Crow Wing, Eighth Crow Wing and Portage lakes in Hubbard County and Moran Creek in Todd County.

In presenting the list, Howard Markus, senior research scientist at the MPCA, said, "The absence of a lake or river from this list doesn't mean it's OK, just that we might not have sampled it yet."

To date, 16 percent of Minnesota's lakes and 10 percent of its streams have been sampled.

More than half of Minnesota's impaired waters have excessive levels of mercury; 99 percent of it comes from the air and 90 percent of the sources of mercury are located outside of Minnesota, Markus said.

Not all impairments are man-made. Some occur naturally, such as when a river flows through a wetland and emerges with low levels of dissolved oxygen. An example is the Mississippi River from Itasca State Park to Bemidji.

"We're convinced it's not a human-induced condition but a natural condition brought on by wetlands and ground water," said Jim Hodgson, MPCA coordinator for the Upper Mississippi River Basin. "We'll recommend a re-classification of that stretch of the river so that it won't be encroached upon by human activity. It could not support a wastewater treatment plant, for example."

A local segment of the Mississippi currently being studied is from its confluence with the Pine River to the mill dam in Brainerd. The study is expected to be finished in 2007, Hodgson said.

Common impairments that can be traced to human activity are excessive phosphorous, which leads to algae blooms, and excessive sediments, which result in turbid water.

A large number of people at the meeting were concerned about Margaret Lake, a 222-acre lake near Lake Shore in Cass County. The lake is part of the Gull Lake chain of lakes. High levels of phosphorous have caused it to be classified as eutrophic, the second lowest clarity level on the four-level Carlson Trophic Status Index.

Target start date for restoration of Margaret Lake is 2014. Many people at the meeting asked if it could begin sooner.

"We're open to discussion on that," Hodgson said. "We'd be glad to have a meeting specifically to explore our options. Most of the time when we're asked to start something sooner we honor that request."

In 1994, phosphorous in Margaret Lake was measured at 60 parts per billion. In 1999, that measurement had dropped to 44 parts per billion. But this past summer the measurement had bounced back up to 58 parts per billion.

"That concerns us," Hodgson said. "Forty-four was a pretty good number and might be the best we can expect from that lake. But we need to determine why it went back up."

Hodgson said he noticed curly-leaf pondweed, an invasive species, on the lake for the first time last summer. He didn't blame it for the higher phosphorous readings, but used the discovery to illustrate that phosphorous management is complicated.

"Bringing a lake around once it's been impaired is not an easy task," Hodgson said.

Steve Moline of Acclaimed Publishers said the former Lake Margaret Lake Association was absorbed by the Gull Area Lakes Association several years ago. He asked for a list of people at the meeting who would be interested in reviving an association specifically for Lake Margaret.

"Talk is cheap," Moline said. "Let's get to work."

Bill Rickmeyer, president of GALA, said Lake Margaret will be the first topic on the agenda at GALA's March board meeting, scheduled for 8:30 a.m. March 4.

VINCE MEYER can be reached at vince.meyer@brainerddispatch.com or 855-5862.